Zoology and wildlife conservation

A general boundary condition for liquid flow at solid surfaces

Article Abstract:

Fluid flow is usually modelled using continuum theories employing mean velocity, pressure and density as variables. However, the continuum method fails to work at the liquid/solid interface, where there are abrupt changes in atom type. A new method, using molecular dynamics simulations, shows a breakdown of the accepted no-slip rule at the liquid/solid interface and reveals the existence of a general nonlinear link between the local shear rate and the amount of slip at the solid's surface.

Liquid marbles

Article Abstract:

Encapsulating an aqueous liquid droplet with a hydrophobic powder produces 'liquid marbles' which act like a soft solid. Gravity was used as a field to move the drop, but it has been established that other weak fields can also drive liquid marbles.

Impact on Everest

Article Abstract:

A way to tune splash behavior when a drop of liquid plummets onto a surface for practical ends is illustrated. Two experiments demonstrate that air is not as passive as is thought to be, and that it can be used for tuning the behavior of drops.